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Abstract:

A marine vessel (100) includes pipes and tubular fluid conduits which are
a part of a waste water management system (102). The waste water
management system includes CPVC piping (104) that is used to transport at
least one of black water or gray water. The CPVC piping meets at least
one fire endurance test set forth by the International Maritime
Organization. Additionally or alternatively, the CPVC piping meets at
least one test set forth in IMO A.653 (16).

Claims:

1. A marine vessel comprising: a waste water system, the waste water
system comprising: a portion of CPVC piping that is utilized in the
transport of one of black water or gray water on the marine vessel.

2. The marine vessel of claim 1 being an offshore oil platform.

3. The marine vessel of claim 1 being a ship.

4. The marine vessel of claim 3 being a military ship.

5. The marine vessel of claim 1 being a passenger cruise ship.

6. The marine vessel of claim 1, wherein said CPVC piping transports
black water to a treatment system.

7. The marine vessel of claim 1, wherein said CPVC piping transports grey
water to a filtration system.

8. The marine vessel of claim 1, wherein said CPVC pipe is marked with an
ink or coating to designate source, preferred use, or certificates held
by the pipe.

9. The marine vessel of claim 8, wherein said ink or coating contains an
optical brightener pigment which is visible by projecting a black UV
light on said marking.

10. The marine vessel of claim 9, wherein said black light emits a
wavelength of from about 200 to about 380 nanometers.

11. The marine vessel of claim 1, wherein said CPVC pipe has a nominal
diameter of from 0.5 inch to 24.0 inches.

12. The marine vessel of claim 11, wherein said CPVC pipe has a nominal
diameter of from 1.5 inch to 8.0 inches.

13. The marine vessel of claim 1, wherein said CPVC pipe and optionally
the fittings meets the requirements of Schedule 40 or Schedule 80 pipe.

14. The marine vessel of claim 1, wherein said CPVC pipe is a composite
CPVC pipe.

16. A method of making a black water or grey water drain system on a
marine vessel comprising: (a) providing multiple lengths of CPVC pipe;
(b) providing at least one drain waste vent fitting made from CPVC; and
(c) attaching said CPVC pipe to said fitting.

17. The method of claim 16, wherein said fitting has a bore which has a
pitch that changes by at least 0.25 inch per foot of length.

18. The method of claim 16, wherein said pipe and said fitting are
attached by the use of a solvent cement.

19. The method of claim 16, wherein said marine vessel is selected from
the group consisting of a ship and an offshore oil platform.

Description:

FIELD OF INVENTION

[0001] This invention relates to fittings, pipes and tubular conduits
which may be classified in U.S. Class 138.

BACKGROUND OF INVENTION

[0002] Cleaning the global water supply is becoming a high priority for
many governing bodies, which are imposing strict environmental
regulations on those doing business on land or at sea. In marine
applications, a significant amount of wastewater can be generated. The
wastewater generated in marine applications may include contaminants such
as fecal coli form, cryptosporidium and giardia, suspended solids and
more, all of which may have a detrimental effect on water quality and the
overall environment. As a result, various marine sanitation treatment
methods, apparatuses, and systems are utilized to lessen the
environmental impact pertaining to wastewater. Example marine sanitation
treatment methods include physical/chemical separation methods,
biological treatment methods, and electrolytic treatment methods.

[0003] Physical/chemical separation involves a flow-through device that
treats liquid waste chemically (Cl2 of NaOCl, for example) and pumps
sewage overboard as permitted. Solids are separated from liquids by a
screen and thereafter macerated and transferred to storage for dumping in
non-restricted zones. This process involves the transportation, storage,
and handling of hazardous chemicals. This process also requires a
relatively large footprint and periodic manual cleaning of the equipment.

[0004] Biological treatment involves the use of microorganisms (bacteria
colonies) to feed on the waste in the presence of oxygen and naturally
digested waste. Large collection tanks receive and aerate the wastewater,
and excess/dead microorganisms with inert sludge are separated by
settling. The clarified liquid from the process is disinfected, typically
with a hazardous chemical, and discharged as permitted. This process can
take approximately 30 hours to complete and requires a relatively large
footprint. The equipment also tends to be heavy, and in periods of low
flow or shutdown the bacterial colonies can be destroyed by the induction
of certain influents. The destruction of bacteria can cause the sewage to
become septic, creating toxic gases such as hydrogen sulphide and
methane.

[0005] Electrolytic treatment systems mix sewage with seawater to flow
through an electrolytic cell. A DC current electrolyses the seawater
creating an oxidant (typically sodium hypochlorite) that oxidizes the
organic material and kills off the disease-carrying pathogens. Due to
increasingly difficult standards associated with wastewater management on
marine vessels, however, improvements in waste water management
methods/apparatuses/systems are desired.

[0006] Black and grey water drain lines on offshore vessels, such as ships
and offshore drilling platforms, is normally made from stainless steel or
expensive metal alloys. The environment these drain lines operate in is
very corrosive. Even though corrosion resistant metals are used,
frequently they must be replaced in 3-5 years because of corrosion. This
replacement can be expensive and require metal working tools to perform
maintenance on the system.

[0007] The metal piping systems used are expensive and heavy. The weight
of the metal systems reduces the "payload" weight the vessel can carry.
Metal piping systems have been required because normal plastic piping
cannot meet the flame and smoke requirements of the applicable standard.

[0008] It would be desirable to have a lighter weight, corrosion resistant
piping system that could handle black and grey water waste on marine
vessels.

SUMMARY OF THE INVENTION

[0009] The following is a brief summary of subject matter that is
described in greater detail herein. This summary is not intended to be
limiting as to the scope of the claims.

[0010] Described herein are various technologies pertaining to marine
vessels, including but not limited to ships, offshore platforms, or other
vessels. With more particularity, the utilization of chlorinated
polyvinyl chloride (CPVC) piping in wastewater applications on marine
vessels is described in greater detail herein. For example, CPVC piping
can be utilized in drain, waste, and vent (DWV) applications on marine
vessels. Additionally, CPVC piping can be utilized in connection with
pressure fittings. CPVC piping can further be used in connection with
transporting gray water and transporting black water on marine vessels.
Gray water can be wastewater received from drains (including sinks and
showers), while black water may include sanitary waste.

[0011] The CPVC piping on the marine vessel may include various joints,
fittings, junctions, and the like. Portions of CPVC piping can be joined
together via a bonding agent, a chemical bond, and/or a mechanical
linkage. The CPVC piping can be utilized to transport wastewater (black
and gray water) to any suitable water treatment system and/or filtration
system, including but not limited to physical/chemical separator systems,
biological treatment systems, and electrolytic treatment systems.

[0012] The CPVC piping described herein can conform to standards set forth
by the International Maritime Organization (IMO) for non-metal piping,
and furthermore can conform to fire test procedures and standards set
forth by the IMO. The CPVC piping described herein is impact resistant,
relatively light weight and resistant to corrosion, and may be used in
both pressurized and vacuum flow applications. When used in a drain
setting, the CPVC piping may have a wall width that conforms to schedule
40 or Schedule 80. Diameter of the CPVC piping when utilized to transport
gray water can typically be between one half inch and up to eight inches,
while diameter of the CPVC piping when utilized to transport black water
can typically be one to eight inches in diameter but may be up to twenty
four inches or larger.

[0013] Other aspects will be appreciated upon reading and understanding
the attached figures and description.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] FIG. 1 is a block diagram of a marine vessel that comprises a
wastewater management system that includes CPVC piping.

[0015] FIG. 2 is a block diagram that illustrates CPVC piping utilized to
transport black water on a marine vessel.

[0016] FIG. 3 is a block diagram that illustrates CPVC piping utilized to
transport gray water on a marine vessel.

[0018] Various technologies pertaining to utilization of CPVC piping in
marine vessels for transport of wastewater will now be described with
reference to the drawings, where like reference numerals represent like
elements throughout. In addition, several functional block diagrams of
example systems are illustrated and described herein for purposes of
explanation.

[0019] With reference to FIG. 1, a block diagram of a marine vessel 100 is
illustrated. The marine vessel 100 may be a ship, a platform such as an
oil platform, or other offshore structure. The marine vessel 100 includes
a wastewater system 102, which can comprise piping, filters, and/or
treatment systems. Example treatment systems that may be included in the
wastewater system 102 comprise physical/chemical separation systems,
biological treatment systems, and electrolytic treatment systems.

[0020] The waste water system 102 comprised CPVC piping 104 is utilized to
transport waste water from a first location on the marine vessel 100 to a
second location on the marine vessel 100. In an exemplary embodiment, the
CPVC piping 104 may be or include a piping system that comprises a
plurality of fluid pipe lengths in fluid communication. The pipe lengths
are formed of a chlorinated polyvinyl chloride (CPVC) composition. The
terms "CPVC composition", "CPVC pipe", and"CPVC piping" as used herein
can mean that the CPVC composition, the CPVC pipe, and the CPVC piping
has a continuous phase of CPVC polymer that has more than 50% by volume
of the polymer components is CPVC, preferably more than 70% and more
preferably more than 80%. Other polymers can be combined with the CPVC
polymer for improving impact resistance, flow enhancers, or other
properties, but these other polymers may be used in smaller amounts,
normally from about 5-15 percent by weight. The CPVC piping 104 can have
a cell class rating of 24448 or 23447.

[0021] The CPVC piping 104 can include pipes, fittings, system joints,
internal and/or external liners, coverings, coatings, and/or the like. A
joint in the CPVC piping 104 includes any suitable method for joining
pipes, including bonding via a bonding agent, chemically bonding,
laminating, welding, etc. For instance, a joint may include a mechanical
linkage between pipes, such as the mechanical linkage described in United
States Patent Application Publication No. 2007/0205004, filed on Aug. 16,
2006, and entitled "SYSTEM AND METHOD OF ASSEMBLY OF CPVC FIRE SPRINKLER
SYSTEM EMPLOYING MECHANICAL COUPLINGS AND SUPPORTS", the entirety of
which is incorporated herein by reference. Fittings can include bends,
elbows, fabricated branch pieces, and/or the like made of CPVC.

[0022] In an example, the CPVC piping 104 may be used in drain, waste,
and/or vent (DWV) applications on the marine vessel 100. Moreover, the
CPVC piping 104 can be utilized to transport black water (sanitary waste)
and gray water (waste water from sinks, showers, etc.) on the marine
vessel 100. The CPVC piping 104 can be manufactured to be a specific
color or set of colors. Thus, CPVC piping utilized to transport black
water can be colored a first color while CPVC piping utilized to
transport gray water can be colored a second color. The invention of the
use of CPVC DWV pattern fittings meeting ASTM D3311, Standard
Specification for Drain, Waste and Vent (DWV) Plastic Fitting Patterns,
aboard marine platforms, ships and other marine floating structures for
the handling of Black and Gray water service and meets the requirements
of IMO International Code for Application of Fire Test Procedures, 1998
(FTPCode) "Test for Surface Flammability", which refers to IMO Resolution
A.653(16) Recommendation on Improving Fire Test Procedures for Surface
Flammability of Bulkhead, ceiling and Deck Finish Materials, piping
materials are held to the same criteria as bulkhead, wall and ceiling
linings. The CPVC piping can be marked with an ink or coating to
designate source, preferred use, and/or certificates which the pipe holds
to indicate it passes certain required tests.

[0023] A particular desirable fitting for the CPVC piping of this
invention is a CPVC DWV fitting described in U.S. Pat. No. 7,178,557,
which is hereby incorporated in its entirety by reference. Such fittings
have a bore which has a pitch that changes by at least 0.25 inch per foot
of length. This tapered bore allows for complete draining of the black or
grey water being transported. The fitting is further described below in
connection with FIG. 4. In one embodiment, the DWV fitting is made to
Schedule 40 or 80 dimensions (primarily wall thickness of the fitting is
adjusted) to correspond to the Schedule 40 or 80 pipe and meets DWV pitch
requirements. Having matching Schedule 40 or 80 dimensions in both the
fittings and the pipe assures complete draining of the black or grey
water.

[0024] Straight lengths of pipe can be connected to the above fitting by
any common means for joining CPVC pipes. The most preferred method of
joining the fitting with the pipe is to use a solvent cement. The solvent
cement is usually made by dissolving CPVC resin in a suitable solvent or
mixture of solvents. These types of solvent cements are commercially
available and thus will not be described further herein.

[0025] Pursuant to an example, the CPVC piping 104 may conform to
standards imposed by the International Maritime Organization (IMO) for
maritime piping systems, fire endurance, flammability, etc. Specifically,
the CPVC piping 104 can conform to standards and test procedures
described in IMO A.735 as well as standards and test procedures described
in IMO A.653.

[0026] The CPVC piping 104 can have sufficient strength to take account of
severe coincident conditions of pressure, temperature, the weight of the
CPVC piping 104, and any static or dynamic load imposed by any portion of
the wastewater system 102. To assure adequate robustness of the CPVC
piping 104, such CPVC piping 104 can have a predefined minimum wall
thickness to assure adequate strength of the CPVC piping 104 for
utilization on the marine vessel 100. The wall thickness of the CPVC
piping 104 can also be selected based at least in part upon expected
handling of the CPVC piping 104, transportation of the CPVC piping 104,
personnel traffic pertaining to the CPVC piping 104, etc. For example,
the wall thickness of at least a portion of the CPVC piping 104 may
conform to schedule 80 (an indicator of wall thickness). Thus, for
instance, drains in the CPVC piping 104 may have a wall thickness that
conforms to Schedule 80. In another example, all piping in the CPVC
piping 104 may have wall thickness that conforms to Schedule 80 or
Schedule 40.

[0027] As indicated above, the CPVC piping 104 can include fittings,
joints, and the like. The fittings, joints, and methods of joining can
meet performance standards imposed on pipes in the CPVC piping 104.

[0028] The CPVC piping 104 can be designed to handle certain amounts of
internal pressure. For example, the CPVC piping 104 can be designed for
an internal pressure not less than a maximum working pressure to be
expected under operating conditions or a highest set pressure on a safety
valve or pressure relieve device corresponding to the CPVC piping 104.
The internal pressure rating for a pipe in the CPVC piping 104 can be
determined by dividing the short-term hydrostatic test-failure pressure
by a safety factor of four or the long-term (e.g., greater than one
hundred thousand hours) hydrostatic test failure pressure by a safety
factor of 2.5, whichever is the lesser. The test failure pressure can be
verified experimentally or by a combination of testing and calculation
methods.

[0029] The CPVC piping can also be designed to handle certain amounts of
external pressure. External pressure can be taken into consideration when
vacuum conditions may exist inside a portion of the CPVC piping 104 or a
head of liquid acts on the outside of a portion of the CPVC piping 104.
The CPVC piping 104 can be designed for an external pressure not less
than the sum of the maximum potential head of liquid outside the pipe
plus vacuum (1 bar). The external pressure rating for a pipe in the CPVC
piping 104 can be determined by dividing the collapse test pressure by a
safety factor of three. The collapse test pressure can be verified
experimentally or by a combination of testing and calculation methods.

[0030] With respect to axial strength pertaining to the CPVC piping 104,
the CPVC piping 104 can be designed such that the sum of the longitudinal
stresses due to pressure, weight, and other dynamic and sustained loads
does not exceed an allowable stress in the longitudinal direction.
Additionally, the CPVC piping 104 can be manufactured/installed while
taking into consideration thermal expansion, contraction, and external
loads.

[0031] The CPVC piping 104 is manufactured such that the maximum working
temperature is at least twenty degrees Celsius lower than the minimum
heat distortion temperature (determined according to ISO 75 method A or
some equivalent) of the resin of the CPVC. The minimum heat distortion
temperature of the CPVC can be at least 80 degrees Celsius.

[0032] Still further, the CPVC piping 104 can be impact resistant, such
that the resistance to impact conforms to applicable standards.

[0033] Moreover, the CPVC can be resistive to environmental effects,
including but not limited to ultraviolet rays, saltwater exposure,
temperature, humidity, etc. Thus, these and other environmental effects
do not degrade the mechanical and physical properties of the CPVC piping
104 below values required to meet IMO guidelines. For instance, the CPVC
piping 104 can be subjected to laboratory aging tests for resistance to
various substances prior to being utilized in the wastewater system 102
as is well understood by those skilled in the art.

[0034] In applications where design loadings incorporate a significant
cyclic or fluctuating component, fatigue of the CPVC piping 104 can be
taken into consideration during installation of such piping 104.

[0035] Still further, the CPVC piping 104 can be resistive to erosion. For
instance, possible effect of erosion can be taken into consideration when
the fluid in the CPVC piping 104 is moving at high flow velocities, has
abrasive characteristics, and/or where flow path discontinuities produce
excessive turbulence. For instance, thickness of walls of the CPVC piping
104 can be increased in such environments, liners can be added, etc.

[0036] The CPVC piping 104 is also configured such that absorption of
fluid by the CPVC piping 104 does not cause a reduction of mechanical and
physical properties of the CPVP piping 104 below those required by the
pertinent standards. The CPVC piping 104 is configured such that fluid
being carried by such piping 104 does not permeate through the wall of
the piping 104. For instance, the CPVC piping 104 may be subjected to
testing for degradation by the fluids it is intended to transport prior
to being utilized in the wastewater system 102.

[0037] The CPVC piping 104 is configured to be compatible with fluid being
carried thereby or in which the piping 104 is immersed, such that the
design strength of the CPVC piping 104 does not degenerate below a
suitable standard.

[0038] The CPVC piping 104 additionally meets fire endurance requirements
set forth by the IMO. The fire endurance of a piping system is the
capability to maintain its strength and integrity (e.g., capable of
performing its intended function) for some predetermined period of time
while exposed to fire that reflects anticipated conditions. The CPVC
piping 104 can conform to at least one of three different levels of fire
endurance. For instance, the CPVC piping 104 can conform to a highest
level of fire endurance, which ensures the integrity of the CPVC piping
104 during a full-scale hydrocarbon fire. Thus, the CPVC piping 104 can
be utilized to carry flammable liquid. In another example, the CPVC
piping 104 can conform to a second fire endurance standard, such that the
CPVC piping 104 can be utilized in systems essential to the safe
operation of the marine vessel 100 after a short fire duration, allowing
the wastewater system 102 to be restored after the fire has been
extinguished. In still yet another example, the CPVC piping 104 can
conform to a third level of fire endurance. Such third level is
considered to provide the fire endurance necessary for a water-filled
piping system to survive a local fire of short duration, and the
functions of the CPVC piping 104 can be restored after the fire has been
extinguished.

[0039] With more detail pertaining to fire endurance of the CPVC piping
104, level one fire endurance is a standard for piping systems essential
to the safety of the marine vessel 100 and those systems outside
machinery spaces where loss of integrity may cause outflow of flammable
liquid and worsen the fire situation. Thus, the CPVC piping 104 can be
designed to endure a fully developed hydrocarbon fire for a long duration
without loss of integrity under dry conditions. For instance, the CPVC
piping 104 can be configured to pass a first fire endurance test
specified by the IMO (described below) for a duration of one hour without
loss of integrity in dry condition.

[0040] Further, the CPVC piping 104 can be configured to meet the level
two fire endurance standard. Thus, the CPVC piping 104 can be designed to
endure a fire without loss of the capability to restore the function of
the CPVC piping 104 after the fire has been extinguished. Thus, the CPVC
piping 104 can pass the fire endurance test specified by the IMO for a
duration of at least thirty minutes in the dry condition.

[0041] Additionally, the CPVC piping 104 can be configured to meet the
level three fire endurance standard. Thus, the CPVP piping 104 can be
designed to endure a fire without loss of the capability to restore the
function of the CPVC piping 104 after the fire has been extinguished.
Therefore, the CPVC piping 104 can be configured to pass a different fire
endurance test for at least thirty minutes in the wet condition.

[0042] The CPVC piping 104 utilized in the waste water system 102 can have
low frame spread characteristics as set forth by test procedures set
forth by the IMO A.653(16) as modified for pipes.

[0043] The CPVC piping 104 can also be static dissipative. Thus, the CPVC
piping 104 can be employed through hazardous areas. That is, the
resistance per unit length of piping, bends, elbows, fabricated branch
pieces, etc. in the CPVP piping 104 does not exceed 1×105
Ω/m and the resistance from earth to any point in the CPVC piping
104 does not exceed 1×106Ω. Pipes and fittings in the
CPVC piping 104 may be made static dissipative by providing a coating of
static dissipative material onto the outside surface.

[0044] In addition, in some instances one or more sections of the CPVC
piping 104 can have fire-protective coating applied thereto to meet the
aforementioned fire endurance standards. In such case, the CPVC piping
can be delivered from the manufacturer with the protective coating in
place, in which case on-site application of protective coating would be
limited to what is necessary for installation purposes (e.g., joints). In
another example, protective coating can be applied on-site. When
protective coating is used, liquid-absorption properties of the coating
can be considered, such that the protective properties of the coating are
not diminished when exposed to salt water, oil, or bilge slops. Further,
the fire-protective coatings that may be applied to the CPVC piping 104
do not degrade due to environmental effects over time, such as
ultraviolet rays, exposure to salt water, temperature and humidity. The
fire-protective coating may also not degrade due to thermal expansion,
resistance against vibrations, and elasticity. Additionally, any coating
applied to the CPVC piping 104 is not subject to flaking, chipping, or
powdering. Moreover, any fire-protective coating applied to the CPVC
piping 104 can meet minimum impact resistance requirements as set forth,
for instance, by the IMO.

[0045] The CPVC piping 104 can be manufactured such that it meets some
suitable standard. For instance, the CPVC piping 104 can meet ISO 9001,
"Quality systems--Model for quality assurance in design/development,
production, installation and servicing", or equivalent standard. The
dimensions and tolerances of the CPVC piping 104 can also conform to a
recognized standard.

[0046] Piping and fittings in the CPVC piping 104 can be marked (e.g.,
permanently) with identification in accordance with a recognized
standard, where the markings include pressure ratings, the design
standard that the pipe or fitting is manufactured in accordance with, and
the material system with which the pipe or fitting is made. Additionally,
each length of pipe in the CPVC piping 104 can be tested at the
manufacturer's production facility to a hydrostatic pressure not less
than 1.5 times the rated pressure of the pipe.

[0047] With respect to installation of the CPVC piping 104 in the waste
water system 102, selection and spacing of pipe supports can be
determined as a function of allowable stresses and maximum deflection
criteria. Spacing of supports of the CPVC piping 104 are not greater than
any recommended spacing provided by the manufacturer. The supports in the
CPVC piping 104 can be selected and placed based at least in part upon
dimensions of pipe being supported, mechanical and physical properties of
the pipe, mass of the pipe and contained fluid, forces, water hammer,
vibration, maximum accelerations to which the CPVC piping 104 may be
subjected, and the type of support.

[0048] Each support can evenly distribute the load of the pipe and
contents thereof over the full width of the support and can be designed
to minimize wear and abrasion. Additionally, heavy components in the
waste water system 102, such as valves and expansion joins, can be
independently supported. Additionally, during installation, suitable
provisions can be made in each pipeline to allow for relative movement
between pipes made of CPVC and other types of piping (e.g., steel) For
instance, differences in coefficients of thermal expansion can be
considered as well as deformation of a ship's hull and/or structure. When
thermal expansions are calculated, the system working temperature and the
temperature at which assembling is performed can be taken into
consideration.

[0049] In some instances, allowances can be made in the waste water system
102 for temporary point loads, wherein such allowances can include at
least the force exerted by a load (person) of 100 kilograms at mid-span
on any pipe of more than one hundred millimeter outside diameter.

[0050] As indicated above, pipes in the CPVC piping 104 can be coupled
using adhesive-bonded, flanged, or mechanically coupled joints. When
adhesives are used, such adhesives can be suitable for providing a
permanent seal between the pipes and fittings throughout the temperature
and pressure range of an intended application. Tightening of flanged or
mechanically coupled joints can be performed in accordance with
instructions of a manufacturer.

[0051] Techniques utilized for joining CPVC pipes can be in accordance
with a defined standard, such as MSC/Circular 449, which requires the
fabrication to be in accordance with the manufacturer's installation
guidelines, IMO Resolution A.753(18) section 4.4.5 and 4.4.6, ASME B31.3
and that personnel performing such tasks be qualified to the satisfaction
of an authoritative body, and that each bonding procedure be qualified
prior to shipboard piping installation commencing.

[0052] After the CPVC piping 104 has been installed, the CPVC piping 104
can be subjected to a pressure test not less than 1.0 times the design
pressure of the system. When utilized in non-essential services, the CPVC
piping 104 can be checked for leakage under operational conditions.

[0053] In some instances, portions of the CPVC piping 104 may need repair
while the marine vessel 100 is at sea. Accordingly, necessary materials
and tools can be placed on board the marine vessel 100. Repairs to CPVC
piping 104 are capable of exhibiting the same mechanical and physical
properties as the original piping.

[0054] Returning again to fire endurance, example tests for establishing
levels of fire endurance are described. The CPVC piping 104 can be
configured to meet one or more of such tests.

Test 1

[0055] Test one is a furnace test with fast temperature increase that is
likely to occur in a fully developed liquid hydrocarbon fire. The
time/temperature of the furnace can be as follows:

[0056] at the end of 5 minutes: 945 degrees Celsius;

[0057] at the end of 10 minutes: 1033 degrees Celsius;

[0058] at the end of 15 minutes: 1098 degrees Celsius;

[0059] at the end of 60 minutes: 1100 degrees Celsius.

The accuracy of the furnace can be controlled as follows: during the
first ten minutes of the test the area under the curve of mean furnace
temperature is not to vary by more than ±15 percent. During the first
half hour of the test the area under the curve of mean furnace
temperature is not to vary by more than ±10 percent of the area under
the standard curve. For any period after the first half hour of the test
the area under the curve of mean furnace temperature is not to vary by
more than ±5 percent of the area under the standard curve. At any time
after the first ten minutes of the test the mean furnace temperature is
not to differ from the standard curve by more than ±100 degrees
Celsius.

[0060] The test specimen can be prepared with joints and fittings intended
for use in the proposed application. The number of specimens can be
sufficient to test typical joints and fittings, including joints between
non-metal and metal pipes and fittings to be used. The ends of the
specimen can be closed. One of the ends can allow pressurized nitrogen to
be connected. The pipe ends and closure can be outside the furnace. The
general orientation of the specimen is to be horizontal and can be
supported by one fixed support with the remaining supports allowing free
movement. The free length between supports is not to be less than eight
times the pipe diameter. To pass the test, the CPVC piping 104 can be
configured with a thermal insulation, which can include a covering. The
test procedure can include the insulation and covering.

[0061] If the insulation includes or is liable to absorb moisture, the
specimen is not to be tested until the insulation has reached an air-dry
condition. An air-dry condition is defined as equilibrium with an ambient
atmosphere of 50% relative humidity at 20±5 degrees Celsius. Special
samples can be used for moisture content determination and conditioned
with the test specimen. These samples can be constructed as to represent
the loss of water vapour from the specimen by having similar thickness
and exposed faces.

[0062] A nitrogen pressure inside the test specimen can be maintained
automatically at 0.7±0.1 bar during the test. The pressure inside the
pipe and nitrogen flow into and out of the specimen can be recorded in
order to indicate leakage.

[0063] During the test, no nitrogen leakage from the sample is to occur.
After termination of the furnace test, the test specimen and the
fire-protective coating, if any, can be allowed to cool in still air to
ambient temperature and then tested to the rated pressure of the pipes as
described above. The pressure is to be held for a minimum of fifteen
minutes without leakage. The hydrostatic test can be conducted on bare
pipe.

Test 2

[0064] Test 2 is a test method for fire endurance of water-filled piping.
A propane multiple-burner test with fast temperature increase can be
utilized. For piping up to 152 mm in diameter, the fire source can
consist of two rows of five burners. A constant heat flux averaging 113.6
kW/m2 (±10 percent) can be maintained 12.5±1 cm above the
centerline of the burner array. This flux can correspond to a pre-mix
flame of propane with a fuel flow rate of 5 kg/h for a total heat release
rate of 65 kW. The gas consumption can be measured with an accuracy of at
least ±3 percent in order to maintain a constant heat flux. Propane
with a minimum of 95 percent purity can be employed.

[0065] For piping greater than 152 mm in diameter, an additional row of
burners can be included for each 51 mm increase in pipe diameter. A
constant heat flux averaging 113.6 kW/m2 (±10 percent) can still
be maintained at the 12.5±1 cm height above the centerline of the
burner array. The fuel flow can be increased as required to maintain the
designated heat flux.

[0066] The burners can be of type "Sievert No. 2942" or equivalent which
produces an air-mixed flame. The inner diameter of the burner heads can
be 29 mm. The burner heads can be mounted in the same plane and supplied
with gas from a manifold. If necessary, each burner can be equipped with
a valve to adjust the flame height.

[0067] The height of the burner stand can be adjustable, and can be
mounted centrally below the test pipe with the rows of burners parallel
to the pipe's axis. The distance between the burner heads and the pipe
can be maintained at 12.5±1 cm during the test. The free length of the
pipe between its supports can be 0.8±0.05 m.

[0068] For the test specimen, each pipe can have a length of approximately
1.5 m. The test pipe can be prepared with permanent joints and fittings
intended to be used. Only valves and straight joints versus elbows and
bends can be subject to testing as the adhesive in the joint is the
primary point of failure. The number of pipe specimens can be sufficient
to test all typical joints and fittings. The ends of each pipe specimen
can be closed, and one of the ends should allow pressurized water to be
connected.

[0069] If any insulation applied to the pipe contains or is liable to
absorb moisture, the specimen should not be tested until the insulation
has reached an air-dry condition (described above). Special samples can
be used for moisture content determination and conditioned with the test
specimen. Such samples can be constructed as to represent the loss of
water vapour from the specimen by having similar thickness and exposed
faces. The pipe samples can rest freely in a horizontal position on two
V-shaped supports. The friction between pipe and supports can be
minimized, and the supports may consist of two stands. A relief valve can
be connected to one of the end closures of each specimen.

[0070] The test can be carried out in a sheltered test site to prevent any
draught influencing the test. Further, each pipe specimen can be
completely filled with deaerated water to exclude air bubbles. The water
temperature is not to be less than 15 degrees Celsius at the start and
can be continuously measured during the test. The water inside the sample
can be stagnant and the pressure can be maintained at 3±0.5 bar during
the test.

[0071] To be accepted as passing the test, no leakage from the samples
should occur except that slight weeping through the pipe wall may be
accepted. After termination of the burner regulation test, the test
sample, together with fire-protective coating (if any) can be allowed to
cool to ambient temperature and then tested to the rated pressure of the
pipes as defined above. The pressure is to be held for a minimum of 15
minutes without signification leakages (e.g., not exceeding 0.2
liters/minute). Where practicable, the hydrostatic test can be conducted
on bare pipe.

Test 3

[0072] A third test can be applied to the CPVC piping 104 to test for
flame spread of the CPVC piping 104. The CPVC piping can be configured to
pass such test.

[0073] Flame spread of plastic piping can be determined by, for instance,
IMO resolution A.653(16) entitled "Recommendation on Improved Fire Test
Procedures for Surface Flammability of Bulkhead, Ceiling and Deck Finish
Materials" with the following modifications. Test can be made for each
pipe material and size. The test sample can be fabricated by cutting
pipes lengthwise into individual sections and then assembling the
sections into a test sample as representative as possible of a flat
surface. A test sample can consist of at least two sections. The test
sample can be 800±5 mm long, and all cuts can be made normal to the
pipe wall.

[0074] The number of sections that are to be assembled together to form a
test sample can be that which corresponds to the nearest integral number
of sections that can make a test sample with an equivalent linearized
surface width between 155 mm and 180 mm. The surface width is defined as
the measured sum of the outer circumference of the assembled pipe
sections that are exposed to the flux from the radiant panel. The
assembled test sample can have no gaps between individual sections.

[0075] The assembled test sample can be constructed in such a way that the
edges of two adjacent sections coincide with the centerline of the test
holder. Further, the individual test sections can be attached to the
backing of a calcium silicate board using wire inserted at 50 mm
intervals through the board and tightened by twisting at the back. The
individual pipe sections can be mounted so that the highest point of the
exposed surface is in the same plane as the exposed flat surface of a
normal surface. The space between the concave unexposed surface of the
test sample and the surface of the calcium silicate backing board can be
left void. The void space between the top of the exposed test surface and
the bottom edge of the sample holder frame can be filled with a high
temperature insulating wool if the width of the pipe segments extend
under the side edges of the sample holding frame.

[0076] The aforementioned tests and procedures corresponding thereto are
described in IMO A.753, the entirety of which is incorporated herein by
reference.

[0077] In addition to the fire endurance tests and the flammability test
described above, the CPVC piping 104 can be configured to pass a variety
of other tests, including but not limited to a non-combustibility test, a
smoke and toxicity test, a test for "A", "B", and "F" class divisions, a
test for surface flammability, amongst other tests. These tests are
described in IMO A.653, the entirety of which is incorporated herein by
reference.

[0078] With reference now to FIG. 2, an example system 200 that
facilitates transporting black water in a marine vessel is illustrated.
The system 200 comprises a portion of CPVC piping 202 that is used in the
transport of black water. A holding tank 204 receives the black water and
is used to retain the black water while or until a waste water process is
undertaken on such black water. In this example system 200, the CPVC
piping 202 can have a diameter of up to twenty four inches or larger.
Additionally, the CPVC piping 202 can be color-coded to indicate that
such piping 202 is utilized in the transport of black water.

[0079] Turning to FIG. 3, an example system 300 that facilitates
transporting gray water in a marine vessel is illustrated. The system 300
comprises a portion of CPVC piping 302 that is used in the transport of
gray water. A filtration system 304 receives the gray water and subjects
the gray water to one or more filtration procedures. The gray water can
be recycled and utilized thereafter on the marine vessel. The CPVC piping
302 can have a diameter of half inch to eight inches. Further, the CPVC
piping 302 can be color-coded to indicate that such piping 302 is
utilized in the transport of gray water. The CPVC piping can also be
marked with an ink or coating to designate source, preferred use, and/or
certificates which the pipe holds to indicate it passes certain required
tests.

[0080] Turning to FIG. 4, an example CPVC piping system 400 that can be
used to transport black or grey water in a waste system on a marine
vehicle. The CPVC piping system 400 has a CPVC DWV fitting 414 used to
connect three CPVC pipes 402. The three CPVC pipes 402 extend into the
receiving flanges 404 of the CPVC fitting. The inside surface of the
flanges 404 are bonded to the outside surface of the CPVC pipe by using
CPVC solvent cement in the contact area 410.

[0081] FIG. 4 also shows an area 406 of indicia. This is shown on the
vertical section of pipe 402, but is preferably on all CPVC pipe
sections. The indicia 408 represented in FIG. 4 as "x" can be letters
that state the pipe's source, preferred use, pipe standards; such as
pressure rating, size, and/or the pipe's compliance with certain
specifications. Since the piping of this invention is intended for use on
marine vessels to handle waste streams, the piping installations have to
be inspected by an official marine agency to assure compliance with the
marine standards and safety requirements such as the United States Coast
Guard, the American Bureau of Shipping, Bureau Veritas, China
Classification Society, Germanischer Lloyd, Det Norske Veritas, Lloyd's
Register, RINA, and other approval and classifying agencies. It would be
advantageous to all of the approval agencies to have an easy way to
identify approved marine piping. This could be accomplished by marking
the pipe with lettering stating the standards the pipe meets. The
lettering could be applied with an ink or coating which contains optical
brightener which would reflect and become visible by the application of a
UV light source, such as a black light. The black light would emit a
wavelength sufficient to cause the optical brightener in the lettering to
become visible. A black light with a typical wavelength of from 200 to
380 nanometer UV emission would make the optical brightener visible. This
would let the inspector know that the pipe meets the required marine
vessel standard.

[0082] The drain, waste, and vent fitting 414 (herein referred to as DWV
fitting), shown in FIG. 4, has a slope or fall built into the bore of the
fitting. The slope of the bore is about 0.25 inch per foot of length. It
is apparent that the distance G1 and G2 are not equal in length. This
difference results in the DWV fitting 414 having a built-in slope. The
slope in the DWV fitting 414 provides for complete draining of the waste
being transported through the piping system. Some typical distances for
G1 and G2 for different size diameter fittings are shown in the table
below.

Different size DWV CPVC fittings could be made other than those shown
above as long as the socket or bore pitch or slope is maintained at about
0.25 inch per foot or greater. In one embodiment, the DWV fitting is made
to Schedule 40 or 80 dimensions (primarily wall thickness of the fitting
is adjusted) to correspond to the Schedule 40 or 80 pipe and meets DWV
pitch requirements. Having matching Schedule 40 or 80 dimensions in both
the fittings and the pipe assures the socket or bore pitch or slope is
maintained and complete draining of the black or grey water is achieved.

[0083] The CPVC pipes 402 are joined to the CPVC DWV fitting 414
preferably by the use of a CPVC solvent cement. CPVC solvent cements are
commercially available from several suppliers such as Oaty and IPS. CPVC
cements are available in hardware stores and plumbing supply stores.
These CPVC solvent cements are typically made by dissolving CPVC resin in
a suitable solvent. Usually the CPVC cement contains from about 15 to
about 25 weight percent CPVC resin. Various other ingredients can be
added to the mixture of CPVC resin and solvent, such as colorants,
thicksotropic agents such as silica, heat stabilizers, and the like.
Usually, these other ingredients are no more than 5-10 weight percent of
the CPVC cement composition. The CPVC cements can be one part cements or
two part cements. When two part cements are used, the first part used is
usually a cleaning solution consisting mainly of solvent.

[0084] To join the CPVC pipe to the CPVC fitting, CPVC solvent cement is
first coated on the outside surface of the pipe and inside surface of the
fitting socket. The end of the pipe is inserted into the fitting socket
and rotated about 90° to assure complete coverage of the cement.
An initial set will occur in about 30 minutes (at 60-100° F.)
which will allow handling and installation of the piping system. Full
cure time will occur in about 1 hour (at 60-100° F., 16-38°
C.) which will allow the piping system to be placed into service. The
initial set time and the full cure time will vary depending on the
ambient temperature and humidity levels of the ambient air. Colder
temperatures and higher humidity levels require longer initial set and
final cure times, which is well understood by those skilled in the art of
installing plumbing systems using CPVC pipe and fittings.

[0085] The CPVC pipe system can have other fittings, such as straight
connectors, elbows and Y fittings. These fittings can likewise be joined
by the use of solvent cement. Mechanical fittings can also be used to
join different lengths of CPVC pipe or to join CPVC pipe to metal pipe.
The mechanical fittings are usually clam shell type structures with a
flexible sealing gasket, such as EPDM rubber, applied to the adjoining
sections of pipe and retained in place by pressure of the clam shell
mechanical device.

[0086] The CPVC pipe shown in this invention specification is an all
polymeric pipe. It should be recognized that CPVC composite pipe could
also be used. CPVC composite pipe has a layer of CPVC on the outside and
inside surfaces and a layer of metal between the outside and inside
layer. Composite pipe, although heavier in weight than straight CPVC
polymer pipe, can have better fire prevention properties and is more
rigid. Composite pipe can be more advantageous for use in small diameter
pipes, such as from 1/2 to 3 inches in nominal diameter pipes. CPVC
composite pipes are commercially available from Lubrizol Advanced
Materials, Inc. of Cleveland, Ohio, U.S.A.

[0087] FIG. 4 shows the direction of flow of the waste in the pipes with
arrows 412. The waste is transported from its source, such as toilet,
sink, or shower, to a receiving point where it is treated for further use
or discharge.

EXAMPLE

[0088] This example is presented to show the performance of the CPVC
piping tested for surface flammability. The CPVC pipe used in the Example
was Corzan® CPVC pipe. One could also use Corzan® HP pipe which
is a higher design basis pressure pipe, if higher pressure or thinner
pipe is desired for a particular application. The screening testing was
conducted in general accordance with Part 5 of the Annex 1 of the
International Maritime Organization (IMO) International Code for
Application of Fire Test Procedures, 1998 (FTP Code), which refers to IMO
Resolution A.653(16). Table 1 shows the pipe material tested.

[0089] The specimens were placed in a conditioned environment maintained
at 23° C.±2° C. and 50%±5% relative humidity until
prior to sample preparation and testing. Each sample measured nominally
804 mm in length and had to be trimmed slightly for testing.

[0090] Before testing, the edges and back surfaces of the test specimen
were wrapped in aluminum foil, backed with 10 mm calcium silicate board,
and placed in a sample holder with the convex face exposed. Sections of
pipe were placed side-by-side to obtain the required width. The sections
were wired to the backer board to secure them into the test frame.

[0091] The testing was conducted in general accordance with Part 5 of
Annex 1 of the IMO FTP Code, i.e., a single specimen of each material was
tested rather than the three specimens by the standard; all other testing
protocols were adhered to. A summary of the test results is provided in
Tables 2 and 3.

[0092] The test results shown in Tables 2 and 3 above were based on one
test instead of the required 3 tests specified in the standard.

[0093] It is noted that several examples have been provided for purposes
of explanation. These examples are not to be construed as limiting the
hereto-appended claims. Additionally, it may be recognized that the
examples provided herein may be permutated while still falling under the
scope of the claims.

[0094] Thus, the exemplary embodiments described herein achieve desirable
objectives, eliminate difficulties encountered in the making and use of
prior systems, solve problems, and attain the desirable results described
herein.

[0095] In the foregoing description certain terms have been used for
brevity, clarity, and understanding. However, no unnecessary limitations
are to be implied therefrom because such terms are for descriptive
purposes and are intended to be broadly construed. Moreover, the
descriptions and illustrations herein are given by way of examples and
the invention is not limited to the exact details shown and described.

[0096] In the following claims, any feature described as a means for
performing a function will be construed as encompassing any means capable
of performing the recited function, and will not be deemed limited to the
particular means shown as performing that function in the foregoing
description or mere equivalents thereof.

[0097] Having described the features, discoveries, and principles of the
invention, the manner in which it is constructed and operated, and the
advantages and useful results attained; the new and useful structures,
devices, elements, arrangements, parts, combinations, systems,
operations, methods, and relationships are set forth in the appended
claims.

Patent applications by LUBRIZOL ADVANCED MATERIALS, INC.

Patent applications in class Cleaning, repairing, or assembling

Patent applications in all subclasses Cleaning, repairing, or assembling